developed a food allergy?

hi
ive never had any food allergies in my life (that i know of) meat, veggies dairy anything! but the strangest thing happens lately when i eat shelled seafood. Living in AU its extremely expensive to eat seafood so usually i would only buy beef chicken or pork. but moving to thailand seafood is not really expensive in comparison, so i started eating seafood basically on daily basis..(thinking that seafood is a much healthier option right? --- wrong!) i was so wrong.. ive developed these rash like symptoms ever since..
is it possible to "develop" an allergy? or could it be something else?

[Soror]

Yes, you can develop food allergies from over-exposure, among other things.  My suggestion, and I am not a doctor, but I have shellfish allergy also, is to eat it only every few days and see if your symptoms lessen?  If not, then stop eating it for a while and then try again in six months.